Investigation of morpho-physiological responses to salinity stress in three promising hybrid genotypes of Iris (Iris germanica L.) inoculated with mycorrhizal fungi

Iris germanica L. is one of the most majestic and popular perennials used in landscape. The aim of this study was comparison of salinity tolerance in three new hybrids genotypes of Iris germanica L. inoculated with mycorrhizal fungi. Treatments consisted of four levels of water salinity (1, 4, 8, and 12 ds/m), three levels of mycorrhizal fungi (0, 15, and 25 g/kg) and three promising genotypes of iris (OPRC-122, OPRC-125, and OPRC-S54). Experiment was conducted based on a factorial and completely randomized design (CRD) with three replications in 2018-2019 in Ardakan University. Some morphological and physiological traits were evaluated. Application of 25 g/kg mycorrhizal fungi at 12 dS/m salinity level increased root length in OPRC122 and OPRCS54 genotypes by 83.77% and 65.38%, respectively compared with control. In OPRCS54 genotype under 8 dS/m salinity, using 25 g/kg mycorrhizal fungi increased the ratio of shoot to root fresh weights by 52.83%. Application of 15 and 25 g/kg mycorrhizal fungi at 12 dS/m salinity in OPRC122 genotype increased P uptake by 341% and 480%, respectively. The use of 15 g/kg mycorrhizal fungi in OPRC125 genotype reduced Na uptake by 32% at 12 dS/m salinity. In OPRCS54 genotype under the same level of salinity, application of 15 and 25 g/kg mycorrhiza fungi decreased sodium uptake by 63.51% and 55.24%, respectively. In general, using mycorrhizal fungi in all three genotypes at salinity level of 8 dS/m reduced the effect of salinity and increased plant yield.